ANALYSIS OF THE PFG-SE NMR EXPERIMENTS IN LYOTROPIC MESOPHASES - THE HEXAGONAL CASE

The NMR Pulsed Field Gradient Spin-Echo method (PFG-SE) may be conveni ently applied to the study of water self-diffusion in lyotropic liquid crystals, giving insight on their molecular organization. The techniq ue has been widely used and mathematical descriptions of the experimen ts have been worked out which, although simple to visualize, may invol ve computer calculations rather cumbersome and time consuming. Here we derive a mathematical expression giving the echo attenuation in a PFG -SE experiment which is formally compact and easy to handle by compute r simulations technique. Its application to hexagonal mesophases is di scussed as an example of how to handle complex situations.